TurboTax does not keep online tax returns longer than 7 years. The IRS destroys all federal tax returns after 7 years unless there are civil or criminal investigations associated with the tax returns.
This is a public Forum, so no one here can tell you...but you'd have to find it yourself anyhow
1) IF you used the Desktop software, then only you would have a copy...even if filed "thru" the TTX servers, a desktop tax preparation is only maintained by you, on your own computer or your own printouts.
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IF you used the "Online" TTX software...don't know if they go back that far...but if they do:
2) If you see those years documents in your current tax account Login in the "Previous Taxes" section, but when trying to actually download them...you may be blocked until you upgrade and pay for PLUS, (or higher) in the 2018 file. But you need to see if the documents years are there first.
3) IF you don't see the documents in your current 2018 Online tax file login, then they "might" be in a UserID account that is different from this one. In that case, you need to log out of any Intuit/TurboTax logins on any browser you have open, and then run the following tool to see if you have another UserID account...then log in there to see what years documents exist.
4) IF #3 shows no other accounts........... or if you find one and login, and it doesn't show those year's documents, then TTX doesn't have those files.
...good luck in your hunt...